Approximately 100 firefighters are battling the blaze near Elephant and Castle station, the London Fire Brigade said in a news release.

Videos posted on social media showed massive plumes of smoke billowing into the air near the station South London, with witnesses reporting that an explosion took place.

The fire service said three commercial units underneath railway arches were on fire, as well as six vehicles and a telephone box. A man is being treated at the scene by paramedics, it added.

"There are significant road closures in place and we are asking people to avoid the area and keep windows and doors closed whilst firefighters work to bring the fire under control," Station Commander James Ryan, who is at the scene, said in a statement.

"The station and nearby buildings have been evacuated."

The cause of the fire is not yet known. However, police have said it is not believed to be terror-related at this stage.

"Officers are supporting @LondonFire in Elephant and Castle," Southwark Police tweeted. "There are significant road closures in place and the public are advised to avoid the area. The incident is not believed to be terror related."

Meanwhile, a nearby theater, Southwark Playhouse, has said it has opened its doors for anyone who has been affected by the fire.

"We are aware of the fire at Elephant and Castle and we hope everyone is OK," Southwark Playhouse tweeted. "If you've been evacuated and need somewhere to go our door is open for you to charge your phone, have some water or take a seat in our bar. We are 77-85 Newington Causeway - two minutes from the station."